* {
  margin: 0;
  padding: 0;
}

ul {
  list-style: none;
}

#tabBox {
  box-sizing: border-box;
  margin: 20px auto;
  width: 500px;  
}

#navBox {
  display: flex;
  position: relative;
  top: 1px;
}

#navBox li {
  box-sizing: border-box;
  margin-right: 10px;
  padding: 0 10px;
  line-height: 35px;
  border: 1px solid #999999;
}

#tabBox>div {
  display: none;
  box-sizing: border-box;
  padding: 10px;
  height: 150px;
  border: 1px solid #999999;
}

#navBox li.active {
  border-bottom-color: #ffffff;
}

#tabBox>div.active {
  display: block;
}
